Tick the respective selection box and the Daylight Layer will overshadow the MarineTraffic Live Map.

No change will affect the areas that are under sunlight. However, a coat of shadow will cover the areas of the world which are not. Notice that the shadow will be lighter in areas that it is dawning or where night is about to come on.

You can get a more detailed view of certain areas by just zooming in (provided you keep the Daylight Layer active).